The purpose of Core A, the administrative/data coordination core is three fold. The first function is to provide the administrative support necessary for a project of this size involving several centers and to establish a clear line of authority and responsibility for decision making. The second purpose of this core is to utilize the facilities of the Clinical Trials Coordination Center (CTCC) under the direction of Dr. Kieburtz to provide data management for Projects 1, 2 and 3. The third critical function is to provide biostatistics support for all three projects through the active participation of Dr. McDermott, the project's chief Biostatistician, in all phases of study planning, execution and analysis.